My laboratory investigations are focussed on identifying genes that may regulate the differentiation of breast cells and to study their role in normal development, carcinogenesis, and tumor progression. Several estrogen receptor positive breast cancer cell lines have been shown to differentiate in vitro in response to a variety of hormones, chemical agents, and polypeptide growth factors. Using these in vitro model systems of differentiation, we are studying the role of known genes in breast differentiation and we are attempting to identify new genes involved in breast differentiation. As potential target gene are identified, their function will be studied to uncover the specific biochemical pathways that govern normal breast development and their role in the development of breast cancer.